1. Field of the Invention
The present invention relates to the field of providing reliable backup power to electrical equipment, e.g., telecommunications switching equipment, servers, which must be climate controlled to avoid malfunction.
2. Description of the Related Art
The conventional telecommunications facility includes a wide variety of computing equipment. For example, telecommunications switches, servers, routers, and other such devices. These devices, when in use, generate heat. This heat must be dissipated in order to avoid malfunction. Furthermore, as more computing capacities are added, the amount of heat generated also increases. Thus, the modernization of equipment has raised the importance level of climate-control issues.
The traditional approach has been to use the existing facility air conditioning systems to climate control equipment by cooling the whole facility, or perhaps by focusing on certain parts of that facility. These AC systems are powered by the facilities existing AC power supply arrangement which functions primarily on AC drawn from a utility company. For emergency situations, the facility usually has some kind of AC backup power arrangement.
A schematic diagram showing a typical prior art arrangement is shown in FIG. 1. Referring to the figure, an ordinary prior art system 10 includes an enclosed area, e.g., an entire facility, a room, or group of rooms, which includes a plurality of pieces of equipment 16 which are computing devices which generate heat. AC power is administered through an AC bus 120. Because the computing equipment 16 consumes DC, the AC must be converted to DC using an inverter 30. The primary source of power to the system is received into bus 32 from an AC utility 14 from outside the facility. Also outside of the facility is a diesel generator 20 which is only active if the AC utility 14 has failed, e.g., in a blackout, or where a power line has been taken out of service. The third and final backup source is a plurality of valve-regulated lead-acid (VRLA) batteries 22 which are included in the DC circuit into which the equipment 16 is incorporated. The VRLA batteries must be stored inside the facility 12 because they cannot endure extreme temperatures.
This AC dependent prior art system has proved disadvantageous in the event both the utility and diesel generator sources of AC are unavailable. The VRLA batteries 22 may provide backup for a limited time, but the facilities air conditioning system cannot draw power from them because it runs on AC. Further, the DC power available from the VRLAs 22 cannot be inverted to power the air conditioning system because the load requirements are too great.
These hurdles have caused operators to simply go without air conditioning and hope for the utility or diesel generator to come back on line before the temperature inside the facility becomes a performance issue or damages the equipment. After that, if the AC sources are too late, the operator must decide whether to shut down, or endure equipment operational problems.